1. Field of the Invention
This invention relates to caulking guns which are manually-actuated guns that are used to dispense caulking material from disposable tubes or cartridges. Such disposable caulking tubes or cartridges are provided with a paper tube for holding the caulking material. One end of the tube is sealed, and the other end is provided with a funnel-like plastic nozzle. These nozzles are molded with closed tips in order to provide an air seal in order to prolong the shelf life of the tube. Also, the inlet end of the nozzle is sealed by a thin diaphragm formed of metal foil or the like. The present invention relates to a caulking gun having a built-in cutter for removing the tip of the funnel-like nozzle of the caulking tube. Moreover, this invention provides an extendible pick built into the handle of the gun for piercing the seal at the inlet end of the nozzle.
2. Description of the Prior Art
For many years, painters and carpenters have opened these caulking tubes or cartridges by carrying a penknife plus a long nail or ice pick. Frequently, the painter is up on a ladder when he is using the caulking gun, and the tube or cartridge is exhausted within a short time, so that the disposable tube needs to be discarded and a new tube loaded into the gun. But the new tube cannot be used until the tip of the nozzle is removed and the seal of the tube is pierced.
The Sherbondy U.S. Pat. No. 3,105,614 shows a standard caulking gun having built into the pistol grip-type handle a shear blade that is mounted on the same pivot as the hollow trigger. This pivoted shear blade cooperates with a plurality of holes formed in an adjacent wall of the hollow handle so as to be able to slice off the tip of the funnel-like plastic nozzle of the caulking tube. One disadvantage of this pivoted shear blade design is that when it wears out, it cannot be replaced easily. Therefore, it becomes inoperative after a certain length of time.
A second patent to Sherbondy is U.S. Pat. No. 3,189,226 which shows a torsion spring fitted between the piston grip-type handle and the pivoted trigger of a standard caulking gun, where one leg of the torsion spring that is in the trigger is elongated to serve as a pick for insertion into the open end of the funnel-like nozzle of the caulking tube. The purpose of this pick is to pierce the seal of the tube adjacent the inlet end of the nozzle. This can only be done by pivoting the elongated leg of the torsion spring out from within the hollow trigger so that the tube may slip between the trigger and the handle, and move towards the pivot of the trigger until the seal of the tube is pierced. Otherwise, the free end of the pick would not be able to reach the seal in the tube because the presence of the trigger would prevent the tube from moving close enough to the pick.
The Reinhardt U.S. Pat. No. 2,659,517 describes a dispenser for coaction with a special container or cartridge for soaps, lotions or toothpaste. The dispenser is preferably designed to be wall-mounted. A cutter-valve member is built into the dispenser to trim off the closed tip of the nozzle of the cartridge, as well as to serve as a control of the flow from the cartridge.